聚氯乙烯（PVC）树脂具有硬而脆的性质，添加粉煤灰（FA）增加PVC复合材料的硬度，劣化加工塑性，从而限制PVC/FA复合材料的使用范围。文章复配使用环保型增塑剂对苯二甲酸二辛酯（DOTP）和三（2-羟乙基）异氰尿酸（THEIC）对PVC/FA复合材料进行增塑以改善其力学性能，考察了DOTP和THEIC复配比例对PVC/FA电缆用复合材料的热稳定性、力学性能和电学性能的影响。结果表明：DOTP和THEIC复配使用可以提高PVC/FA电缆复合材料的热稳定性和力学性能。同时加入29份DOTP和1份THEIC时，PVC/FA2复合材料的断裂伸长率为107.98%，与未添加增塑剂的复合材料相比，断裂伸长率提升了105.31%，第一阶段和第二阶段热分解温度分别提升了11.1 ℃和6.0 ℃，复合材料的加工性能得到显著提升。

Polyvinyl chloride (PVC) resin is hard and brittle. Adding fly ash (FA) will increase the hardness of PVC composites and deteriorate the processing plasticity, thus limiting the application range of PVC/FA composites. Dioctyl terephthalate (DOTP) and tris(2-hydroxyethyl) isocyanuric acid (THEIC) were used to improve the mechanical properties of PVC/FA composites. The effects of the ratio of DOTP and THEIC on the thermal stability, mechanical properties and electrical properties of PVC/FA cable composites were investigated. The results show that the combination of DOTP and THEIC can improve the thermal stability and mechanical properties of PVC/FA cable composites. When adding 29 phr DOTP and 1 phr THEIC at the same time, the elongation at break of PVC/FA2 composite is 107.98%. Compared with the composite without plasticizer, the elongation at break of PVC/FA2 is increased by 105.31%. The thermal decomposition temperature in the first stage and the second stage of PVC/FA2 is increased by 11.1 ℃ and 6.0 ℃ respectively, and the processability of the composite is significantly improved.